Stackable chair



FIG. 1 is a perspective view of the stackable chair taken from the front and the left side;

FIG. 2 is a front elevation of the stackable chair;

FIG. 3 is a rear elevation of the stackable chair;

FIG. 4 is a left side view of the stackable chair, the opposite side being a mirror image thereof; and,

FIG. 5 is a top view of the stackable chair. 

The ornamental design for a stackable chair, as shown and described. 